Problem/Purpose: Over 21.5 million Americans experience co-occurring substance use disorder and mental illness, particularly depression, leading to poor health outcomes and increased healthcare costs. There was no regular depression at an urban opioid use disorder clinic despite a 2020-2021 survey showing 63.9% of respondents met depression criteria. The purpose of this quality improvement (QI) project was implementation of annual depression screening using the Patient Health Questionnaire 9 (PHQ-9) and treatment referral for those positive. The project expected to impact 60 patients. Methods: QI Project Lead worked with two clinic leaders, three nurse practitioners (NPs) and four staff on structure/workflow changes. The QI project utilized Expert Recommendations for Implementing Change (ERIC) Strategies: accountability, communication, major structure change, data, and education. Examples of strategies included: (a) medical record modification, (b) NP training on screening/referring/completing PHQ-9, (c) “PHQ-9 Screening for Depression Policy” implementation, (d) education/training on workflow changes, and (e) weekly chart audits with provider feedback. Results: Eighty-one patients were eligible for PHQ-9 screening. Of those eligible patients, 80.20% (n=65) had a completed PHQ- 9. Of the 23.10% (n=15) with depression, 100% had a documented treatment plan. Treatment referrals showed 60.00% (n=9) already in care, 6.70% (n=1) referred to team psychiatrist, 26.70% (n=4) to a community referral, and 6.70% (n=1) refused referral. Conclusion: Findings show the QI project achieved its goals. The OUD clinic successfully incorporated depression screening/referral into the clinic workflow. Practice implications include alignment of project and clinic mission, provider buy-in, built-in documentation requirements, and provider feedback. Provider feedback highlighted the need of clinical judgement in PHQ-9 administration timing.